The present invention relates generally to cooling of heated products, and more particularly, concerns a showering system and method for conserving the use of coolant in cooling cooked food products, such as meats.
In producing certain processed meat products, such as frankfurters, sausages, cold cuts, and certain solid meat items, it is the conventional practice to cook or smoke the product and then to cool it rapidly by showering, so that heat is uniformly extracted from its surface. Typically, a quantity of the product is mounted on open racks for cooking or smoking. The racks are usually arranged to be movable as a result of having wheels, or the like. In this manner, a rack of product is conveniently brought into a smokehouse or large oven and left there for the duration of the cooking or smoking process. Upon completion of that process, the rack can then be transported to a shower and cooled appropriately.
Typically, the cooling shower utilizes tap water as a coolant, because of its ready availability and relatively low cost and general availability. However, an ever present problem in this industry has always been the large quantity of water which is utilized in cooling the cooked product. It has been suggested that a substantial reduction in water consumption could be achieved by recirculating the water within the shower. Although this has proved effective in closed systems, it has generally been inapplicable in meat processing plants. One of the primary difficulties has been that the racks of product are moved along the factory's floor which is a contaminated surface. In addition, it is necessary for workers who transport the racks of product to walk within the shower stalls and upon the floors thereof. Water used to shower the product which falls upon the contaminated rack wheels and/or the shower floor, becomes contaminated. If this water were then recirculated in unpurified form and used to shower the product, the food product itself would become contaminated. Thus, the meat processing industry has long avoided coolant recirculation in systems with movable racks.
In copending U.S. patent application No. 14,308 filed Feb. 23, 1979, which is assigned to the assignee of the present patent application, Rudolf Maurer discloses that more efficient showering of heated products and an improvement in the product itself can be achieved by intermittent showering. Specifically, Maurer discloses that more rapid cooling and effective tempering of the surface of the product are achieved by repeated, intermittent showering by showering the product for a specified period of time followed by a period during which the shower is turned off and during which heat is transmitted from the core of the product to heat its surface. In practice, it has been found that cooling and conditioning products by this process can be substantially consistently achieved by considering the size of the product, its initial (hot) temperature and the temperature of the tap water. Specifically, excellent results could be obtained by determning the on and off times of the shower from a table which considered the product characteristics, the desired temperature change and the temperature of the tap water. However, it becomes difficult to obtain consistent results in a system where the coolant is recirculated because the temperature of the coolant changes during the process, unlike tap water which has a relatively constant temperature over long periods of time.